In general, a machining tool mounted with a cutting insert is used in the field of cutting machining such as drilling, milling, and turning. A cutting insert used in heavy-duty machining requiring high depth of cut and feed rate experiences large vibrations caused by high cutting resistance, leading to decreased tool life. Moreover, the market nowadays demands higher productivity, so both roughing and finishing operations need to be conducted simultaneously without changing the insert. Therefore, there has been wide demand for cutting inserts which have excellent chip control for high depth of cut and feed rate as well as for small cutting conditions, and are adaptable for a wide range of machining operations for roughing and finishing, without excessively increasing the cutting resistance.